Thomas Alva Edison

Edison, Thomas Alva, 1847–1931, American inventor, b. Milan, Ohio. A genius in the practical application of scientific principles, Edison was one of the greatest and most productive inventors of his time, but his formal schooling was limited to three months in Port Huron, Mich., in 1854. For several years he was a newsboy on the Grand Trunk RR, and it was during this period that he began to suffer from deafness, which was to increase throughout his life. He later worked as a telegraph operator in various cities.

Edison's first inventions were the transmitter and receiver for the automatic telegraph, the quadruplex system of transmitting four simultaneous messages, and an improved stock-ticker system. In 1877 he invented the carbon telephone transmitter (see microphone) for the Western Union Telegraph Company. His phonograph (patented 1878) was notable as the first successful instrument of its kind.

In 1879, Edison created the first commercially practical incandescent lamp (with a carbon filament). For use with it he developed a complete electrical distribution system for light and power, including generators, motors, light sockets with the Edison base, junction boxes, safety fuses, underground conductors, and other devices. The crowning achievement of his work in this field was the Pearl St. plant (1881–82) in New York City, the first permanent central electric-light power plant in the world. He also built and operated (1880) an experimental electric railroad, and produced a superior storage battery of iron and nickel with an alkaline electrolyte.

Other significant inventions include the Kinetoscope, or peep-show machine. Edison later demonstrated experimentally the synchronization of motion pictures and sound, and talking pictures were based on this work. During World War I he helped to develop the manufacture in the United States of chemicals previously imported; he also served as head of the U.S. navy consulting board concerned with ship defenses against torpedoes and mines. Edison later worked on the production of rubber from American plants, notably goldenrod.

Edison held over 1,300 U.S. and foreign patents, and his workshops at Menlo Park (1876) and West Orange, N.J. (1887), were significant as forerunners of the modern industrial research laboratory in which teams of workers, rather than a lone inventor, systematically investigate a given subject. An Edison memorial tower and light was erected (1938) in Menlo Park, N.J.; Edison's laboratory and other buildings associated with his career are preserved or replicated in Greenfield Village. Some of his various companies were consolidated to form the General Electric Company (GE).